Originally Posted by Grizz
Trying to figure head loss will cause hair loss. Rule of thumb match the return to the over flow. Unless you have a long run or a lot of elbows it wont matter
It's not that difficult. The calculator on reefcentral is super easy to use. Simply picking a pump that is rated to 700 gph
just like overflow means you will end up with an undersized pump. A mag 7(700 gph
) moving water just 3 feet vertically with no elbows looses 200 gph
due to headloss. 3 feet isn't far. Use the calculators.
In the end go bigger with ball valve or bypass to dial down the gph
to match overflow.